I. Field of the Invention
This invention relates generally to methods of fabricating angiographic catheters or the like, and more particularly to methods of forming a soft, deformable tips at the distal end of such catheters.
II. Discussion of the Prior Art
In a co-pending patent application of Robert A. Van Tassel, et al, Ser. No. 520,996, filed Aug. 8, 1983, now Pat. No. 4,531,943, and assigned to the assignee of the instant application, there is described a catheter construction wherein a pre-molded soft, deformable tip is suitably bonded to the distal end of a catheter body so that when the catheter is later passed into the vascular system of a patient, there would be less trauma to the blood vessel occasioned by the introduction of the catheter. To create a smooth, yet reliable joint between the soft-tip member and the catheter body, it has been the practice to grind the exterior surface of the catheter body on a centerless grinder to create a zone of lesser thickness proximate the distal tip of the catheter stock and then to form a lap joint by fitting the pre-formed, soft-tip member onto the so-prepared end portion where it is held in place by a suitable adhesive or other known bonding technique. This process has proven to be somewhat slow and, considering the cross-sectional dimensions of angiographic catheters, slight variations in the wall thickness occurring during the centerless grinding operation can render the resulting catheter unacceptable, thus decreasing the manufacturing yield and increasing the per catheter cost.
The methods comprising the present invention allow the formation of the soft, deformable tip on the end of a catheter body in a comparatively inexpensive manner, while producing high yields of usable catheters.